1. Field of the Invention
The invention relates to molten glass recirculating apparatus and systems and, more particularly, to a bubbler apparatus for a glass melter that provides enhanced glass recirculation.
2. Description of the Related Art
Air bubblers have previously been used in glass melters. In general, these bubblers comprise air tubes for injecting air bubbles into the free glass pools. A disadvantage of such air bubbles is that liquid flow velocities imparted by the bubbles are lost in the localized liquid recirculation. The need to provide recirculation and agitation of molten glass is well documented and a number of issued patents relate to this problem. Considering some of these patents, U.S. Pat. No. 6,334,337 to Macedo et al. relates to an air bubbler for increasing the glass production of a glass melt, wherein a plurality of bubblers are provided and a precious metal insert is used to protect each of the bubblers from corrosion at the orifice or orifices thereof through which air is injected into the melt.
U.S. Pat. No. 5,868,814 to Lin also relates to apparatus for recirculating molten glass. A gas emitter pipe releases air into a riser chamber having a lower inlet, opening and an upper, outlet opening so that molten glass within the riser chamber rises and exits through the upper opening and along a trough. The exiting molten glass causes additional molten glass to be drawn into the riser chamber through the lower inlet opening.
Other patents disclosing glass melters including gas (air) bubblers include U.S. Pat. No. 6,085,551 to Piper et al. U.S. Pat. No. 4,718,931 to Boettner, and U.S. Pat. No. 4,600,425 to Krumwiede et al.